ST7LITE25F2 STMicroelectronics, ST7LITE25F2 Datasheet - Page 24

• Manufacturer Part Number: ST7LITE25F2
• Description: 8-BIT MCU WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, TIMERS, SPI
• Manufacturer: STMicroelectronics

Specifications of ST7LITE25F2

• 8 Kbytes Single Voltage Flash Program Memory With Read-out Protection, In-circuit Programming And In-application Programming (icp And Iap). 10k Write/erase Cycles Guaranteed, Data Retention: 20 years at 55˚C.
• Clock Sources: Internal 1% RC oscillator, crystal/ceramic resonator or external clock
• Five Power Saving Modes: Halt, Active-Halt, Wait and Slow, Auto Wake Up From Halt

ST7LITE2
PHASE LOCKED LOOP (Cont’d)
Figure 12. PLL Output Frequency Timing
Diagram
When the PLL is started, after reset or wakeup
from Halt mode or AWUFH mode, it outputs the
clock after a delay of t
When the PLL output signal reaches the operating
frequency, the LOCKED bit in the SICSCR register
is set. Full PLL accuracy (ACC
a stabilization time of t
13.3.4 Internal RC Oscillator and
Refer to
of the LOCKED bit in the SICSR register.
24/133
1
4/8 x
input
freq.
t
STARTUP
section 7.6.4 on page 33
t
LOCK
STARTUP
STAB
LOCKED bit set
(see
t
PLL
.
STAB
) is reached after
PLL)
for a description
Figure 12
t
and
7.3 REGISTER DESCRIPTION
MAIN CLOCK CONTROL/STATUS REGISTER
(MCCSR)
Read / Write
Reset Value: 0000 0000 (00h)
Bits 7:2 = Reserved, must be kept cleared.
Bit 1 = MCO Main Clock Out enable
This bit is read/write by software and cleared by
hardware after a reset. This bit allows to enable
the MCO output clock.
0: MCO clock disabled, I/O port free for general
1: MCO clock enabled.
Bit 0 = SMS Slow Mode select
This bit is read/write by software and cleared by
hardware after a reset. This bit selects the input
clock f
0: Normal mode (f
1: Slow mode (f
RC CONTROL REGISTER (RCCR)
Read / Write
Reset Value: 1111 1111 (FFh)
Bits 7:0 = CR[7:0] RC Oscillator Frequency Ad-
justment Bits
These bits must be written immediately after reset
to adjust the RC oscillator frequency and to obtain
an accuracy of 1%. The application can store the
correct value for each voltage range in EEPROM
and write it to this register at start-up.
00h = maximum available frequency
FFh = lowest available frequency
Note: To tune the oscillator, write a series of differ-
ent values in the register until the correct frequen-
cy is reached. The fastest method is to use a di-
chotomy starting with 80h.
CR70 CR60 CR50 CR40 CR30 CR20 CR10 CR
purpose I/O.
7
0
7
OSC
0
or f
OSC
0
CPU =
/32.
CPU =
0
f
OSC
f
OSC
/32)
0
0
MCO
SMS
0
0
0